Answer: 6 students
What we know:
Students: 24
Students who play checkers: 
Students who also play sudoku:
of the 
24 ÷ 3 = 8, so 8 × 2 = 16 (students who play checkers)
× 2 = 
So the answer is,
6 students play both checkers and sudoku
There are 20 miles is Sheng from his home.
If we were to draw a best fit line, the y-interest would be near 15, and the slope would be negative.
In the options given, the slope is either -3 or -13. If we imagine a line through the plotted points, the rise would be about 15 while the run would be about 5. This means the slope is about -3.
The best answer is y = -3x + 15
Its a 50/50 chance because a coin only has 2 side
Your scale model will be just under 3.135 inches x 1 inch even.